Possession
by Mlzu
Summary: Demons feed on lust. They feed on pain and dark feelings within humans. Shinya accidently falls under Byakkomaru's control when he is emotionally weak. And Guren becomes the victim. What if Byakkomaru is a possession type demon? Takes place at the end of ONS Season 1.


**SUMMARY** : Demons feed on lust. They feed on pain and dark feelings within humans. Shinya accidently falls under Byakkomaru's control when he is emotionally weak. And Guren becomes the victim.

What if Byakkomaru is a possession type demon? Takes place after the mission in Shinjuku and before Shinoa comes to see Guren in the laboratory (ONS Season 1, final episode).

 **WARNING** : This fic is rated explicit because of its dark themes (possession, domination, manipulation & possibly rape)! Please refrain if you're uncomfortable with such contents.

 **DISCLAIMER** : Owari no Seraph belongs to its rightful owner(s).

 **A/N** : Seriously you're going to read this? Last warning though, there's no hot smut! This is not a romance/love story! This is about human falling into possession of demon! There's only pain and hints of painful sex! Last chance to change your mind! Don't say I never warn you! I do not tolerate flame!

Proceed?

On with the story! Read with open mind!

* * *

 _"Shinya."_

 _"Hey, Shinya."_

 _"Shinya~"_

The light was off. Then it was on. Then it was off again. Then it flickered twice, thrice, before it came back full alive. The light was back in the room.

The temperature in the room dropped slightly.

Shinya lifted his eyes away from the book he was reading. He felt a weak blow at his ear.

"What is it, Byakkomaru?"

Lightning sparked around his rifle.

Shinya was alone in his office after the rescue mission in Shinjuku. It was night, he was not needed at the moment and here he was, in his office at the headquarters in Shibuya, with his favourite activity to kill his time.

 _"Shinya."_

It was that voice again. Another blow at his ear.

 _"Hey, Shinya."_

"Byakkomaru, I'm listening."

There was a laughter.

 _"Hey, Shinya. I'm hungry."_

 _You barely use me. You barely respond to emotion either. I need something to justify my hunger._

"Really?"

Shinya was back to his book like he had never been interrupted. He had a hunch of where this was leading to. He should not fall into the demon's temptation.

Byakkomaru glanced over Shinya's shoulder, peeking at the content of the book. He smiled then.

Byakkomaru knew his master's weakness.

Guren Ichinose.

 _"Hey, Shinya?"_

"Hmm?"

Shinya's eyes remained glued to the book. He had no real intention to deal with the demon.

 _"Doesn't it bother you?"_

Big, white tiger's head suddenly appeared before Shinya, giving him a slight jolt.

Byakkomaru. The demon resided within his sniper which took the form of a tiger. His body was covered with white fur with dark stripes and he was gifted with a set of big, milk-like coloured eyes. The possession type.

A pair of clear, whitish eyes was staring at him, watching mischievously.

"What?"

With Byakkomaru's head covering his book like that, it was impossible for him to continue his reading. Maybe he should as well give up and give Byakkomaru his attention.

 _"Don't you find it strange?"_

"What is strange?"

Byakkomaru's smile stretched. It seemed his master was playing dumb with him.

Not a problem. He should play along too.

He was a demon after all.

Demons were full of mischiefs.

 _"Seems like your best friend is scheming something. Do you know anything of this?"_

Shinya frowned.

"Your point?"

 _"Keeping you in the dark and chasing you away, isn't he abandoning you?_

 _Abandoning me? His friend?_

"What? No, Guren isn't like that -"

Byakkomaru smirked inwardly. His master was slowly reacting to him. Play his cards right and Shinya Hiragi would fall under his control. All he needed was a gentle push.

 _"But why must he avoid you?_

"When has he ever avoided me?"

Byakkomaru heaved a sigh. He gave Shinya a pathetic smile.

 _"You can keep playing ignorant with me. But you can't keep lying to yourself."_

He leaned closer to Shinya.

 _"Play dumb and you'll be left alone again."_

Shinya was greatly affected at the word 'alone'. His heart would throb just at the mention of it. His eyes moving wildly as if shaking.

Byakkomaru slung his arm around Shinya's head and covered his eyes with his furry hand.

Shinya Hiragi was collapsing.

 _That's right…_

 _"Let me possess you, Shinya."_

The light flickered again.

* * *

Byakkomaru smirked. He found his reflection on the mirror. He was in his master's body. Knowing well Shinya was unconscious inside him, he purred.

"Sleep for a while, Master~"

* * *

Knock. Knock.

Guren cringed.

The door was opened.

"Hiya~ It's me, Guren!"

Shinya poked his head from the door. He had a big grin plastered on his face.

Guren clicked his tongue.

"What is it, Shinya? I don't have time to play with you!" he said roughly. On his desk laid pieces of paper, undoubtedly JIDA's official reports.

"So harsh, Guren~" He frowned and stepped in. "I came to check on you! And here I bring you coffee too!" He put the cup on the table.

Guren stared at the dark liquid with mixed feelings. Sure, he needed coffee but if he drank it at this hour, he was going to have trouble sleeping later.

Guren frowned.

"Coffee?"

"Are you saying no to coffee?"

"No! That's not the question-"

"Then, drink it." Shinya pushed the cup closer to Guren.

Guren's eye twitched in irritation.

"Fine, I'll drink it later!"

Shinya smiled sweetly. His dark haired friend was back to his work. He walked behind Guren's chair.

Shinya bent his body slightly, trying to take a peek at the reports. He tucked his side bangs that had gotten in the way behind his ear, curious eyes on the piece of paper.

"What is this?"

Guren startled. He kept the reports away from Shinya's view.

Shinya tilted his head to the side.

"Are you hiding something from me, Guren?"

"None of your business!" He glared.

Shinya laughed while he straightened his body, overjoyed by Guren's grumpiness.

"You're grumpy! I think you're caffeine-deprived?"

Guren's face contorted in annoyance. He glanced at the coffee that Shinya made and arched an eyebrow at him.

"Caffeine-deprived, huh?"

He grasped at the cup, brought it up to his mouth and gulped the liquid down in one go, missing the widening grin on Shinya's face. He put the empty cup back on its saucer.

He was about to smirk in triumph at Shinya but all of sudden he was attacked with a strong throb at the head. He put his hands at his head. He felt like collapsing. His vision was blurring. Everything around him was spinning.

"You bastard! What did you put in the drink?!"

Dizzy, Guren rested his head on the desk.

He was losing his consciousness but before he went completely black, he caught a glimpse of canine through 'Shinya's grin. That second, Guren knew he had fallen victim to the trap set by Shinya's demon.

"B – Byakkoma…"

* * *

Guren woke up to find Shinya – Byakkomaru unbuttoning his shirt. His uniform was no more, lying forgotten on the floor. Shinya was no longer in his JIDA uniform. Only the shirt he wore underneath was on, which had been completely unbuttoned.

Byakkomaru focused on his task. Apparently he had the idea that Guren had regained his consciousness because from time to time, he would throw a heated stare at Guren. Done, he exposed Guren's skin by flapping his shirt wide open.

His pants were kept in place, however.

Shinya put his fingertip between his teeth and began to peel off the glove from his hand. Once out, like a cat, he threw it away to the side with his mouth. Then he proceeded with another glove.

Done, his focus was back on Guren. He rested his hand on Guren's exposed skin, feeling and pressing the muscles with the pads of his fingers.

"Stop it!" Guren glowered.

"Try me," Byakkomaru said, bored.

"Shit, Byakkomaru, stop!" Guren attempted to break free. While he was out, Byakkomaru had his hands handcuffed at the bedframe. His hands were useless now. He struggled again but every attempt was met with failure. Instead his energy was draining. Frustrated, he shouted, "Shinya will never do this!"

"Of course he won't," Byakkomaru answered, playing with Guren's chest. "That's why I'm doing this (in his stead)." He lifted his eyes and added, "For him."

Panic was arising inside Guren. Byakkomaru was not playing around. He must stop this before it was too late. Or both he and Shinya were going to regret this.

Swallowing the lump in his throat, Guren tried again, desperate.

"He will never want this!"

Byakkomaru snorted. With one finger, he tucked Shinya's threads behind the ear and mounted Guren, straddling him at the hips. His eyes never left Guren's, putting Guren under his spell through his deep, penetrating stare.

* * *

Guren gasped for breaths. The hand around his neck was tight. Byakkomaru was choking him with a deathly grip but not tight enough to end Guren's life. It was just enough to make him suffer from the lack of air. Guren could not die yet.

Guren choked. His lungs were almost empty. He tried to gasp for air again but it felt like his breathing channel was being crushed. Byakkomaru was watching him with scrutiny eyes. Watching every little move that he made.

Guren stared back at Byakkomaru. His vision almost painted with black. He was certain he was about to pass out again, if he did not die by the lack of air tonight. The grip around his neck was firm it sure would leave a bruise behind.

The moment Guren's eyes were about to slide close, Byakkomaru's grip loosened.

Guren opened his eyes again, chest heaving from laboured breaths. His heart now rapidly pumping blood rich in oxygen throughout his body.

The torment did not end here.

Byakkomaru dragged his fingers along Guren's jaw. He touched and caressed Guren's chin with his thumb.

What was it with this man that his master who was usually calm and composed could shake whenever the topic of Guren Ichinose was brought up?

What was it with this man that could make his master smile genuinely whenever he was around?

Who was this man, admired by his master, respected by others, but weak under his control?

Byakkomaru did not understand. Did not want to understand even, at the bright and colourful mood surrounded his master when Guren was within his reach.

All he needed were pain, lust, wrath and greed to feed his hunger. To become stronger.

Once satisfied, he straightened his body.

"Beautiful, isn't it?" He ran his hand along Shinya's neck down to his chest. He was trying to make Guren fall into his sweet temptation. Byakkomaru knew it took more effort than a simple threat to make someone like Guren to crumble on his knees. Luckily, Byakkomaru knew friendship was one of Guren's weaknesses.

Gritting his teeth, Guren refused to allow the demon to win in this twisted game of his. He locked his eyes with Byakkomaru's, refusing to follow the direction of his hand. He struggled again, in hope the chains would break. The metals met with noisy clanks.

Byakkomaru grinned at Guren's strong-willed.

"This body which has never been touched, has never been marked by anyone, don't you want it? Guren Ichinose?"

"Bastard…I will never…take him like that! He's my friend!" Between the pains, Guren barked. Be damned if Shinya heard him call him friend. Be damned if Shinya was going to harass him nonstop. For keeping his heart shut. For being dishonest with his feelings.

Because for once, Guren wanted Shinya to hear him, wanted him to wake up.

"Oi, Shinya! Wake up!"

"A friend?" Byakkomaru laughed mockingly at him. Shinya looked ugly under Byakkomaru's control. "Then, what is this, Guren Ichinose?" He ran his hand downwards and cupped at his clothed arousal, turning his body slightly in the process.

Guren flinched at the touch.

"You got an erection!" Byakkomaru said out loud. "A friend shouldn't get an erection because of another friend!"

Guren snorted mockingly.

"Then? What about you?" he pulled a smirk. "Isn't that an erection too? Do you love torturing me so much that you get a hard on? Or is it Shinya?"

Byakkomaru was shocked at the turn of events. Shinya's cock was pocking at Guren's stomach. Since when did Shinya regain his consciousness? Too surprise at the discovery, Byakkomaru accidently lowered his guard down and Shinya seized the opportunity to take over his body.

Shinya squeezed his eyes tight. His vision was blurry. His head was throbbing like crazy. He took in a couple of deep breaths to calm himself down. After a few moment, he opened his eyes again.

"G-Guren?"

Guren's eyes shot open at the voice.

"I-"

Shinya was at a loss for words, too speechless at Guren's condition.

"Shinya, break the chain!"

Shinya bent over to release Guren from the handcuffs. That moment when he was too focused on his task, Byakkomaru managed to take control of his body again.

"Human…!" Byakkomaru cursed, shaking his head a bit.

Guren smirked in triumph.

"See? I think Shinya is fighting for control. You might want to be more careful from now on."

The light emitted from the lightning in the dark sky passed through the window and entered the room, giving it a quick source of light. With the help from the light, Guren caught a glimpse of Shinya's face staring down at him with rage. He was pissed.

Byakkomaru snorted.

"Don't worry, it won't happen again." His eyes were plain cold, glowing in the dim room. "Even if it's going to, I'll make sure you get a taste of your friend's body. Doesn't it sound like a good idea?"

Without warning, Byakkomaru leaned over at his ear.

"Ready now, Guren Ichinose?"

 _Shit!_

Too late. Byakkomaru licked at his ear and without giving Guren any chance to protest, he crushed their lips together.

* * *

Guren cursed at Byakkomaru inwardly.

Byakkomaru was calling his name.

He kept calling his name, mimicking Shinya's way of speak when the time was ideal just to make him lose his mind. Calling and whispering his name at one time in false pain and at another time in mock pleasure. It was killing him.

It was not exactly an act of mimicking to be honest since Byakkomaru did talk with Shinya's voice.

When Byakkomaru lowered down on him, he felt terribly bad for Shinya. Guren was aware he could not avoid this anymore. He was battered. He was exhausted. There was no way fighting this. It was hopeless.

Of course Byakkomaru would not feel anything. It was Shinya's body. It was Shinya who would experience the pain from being penetrated dry. However, it was exactly the twisted pain that the demon wanted. Even if it was going to rip the host's body apart.

With cold, blank stare, Byakkomaru ran his fingers across Guren's skin. He stopped midway. He brought his eyes staring into Guren's violet ones. With their eyes on each other's, he clutched at the skin. Then his eyes were back on where his fingers at. With his nails buried into the chest, he slowly dragged his sharp nails across Guren's skin in torturous manner until he reached the stomach.

Angry red trails glowing in the dull room, tainting and marking Guren's tanned skin. Guren's face twisted. He was bearing the stings.

Byakkomaru's eyes were on him again. At Guren's twisted face, he grinned. Then he began to ride Guren with Shinya's body.

Guren hissed. Shinya was tight around him. His arms were numb. He was helpless.

"Aren't you enjoying me, Gurennn~"

 _Shinya, wake up!_

* * *

Guren woke up to feeling sticky. Sticky with dried sweats and semen. The room reeked of sweat and sex. His brain was numb. His entire body was sore. His head felt heavy.

He realized he was still in Shinya's room.

His hands had been released. Guren remembered just before he passed out, Byakkomaru had unhandcuffed him before he kissed him at the corner of his lips and whispered with Shinya's voice.

 _"Sleep tight, Guren~"_

He lowered his eyes. Shinya's crown of snowy hair covered his view. His head was comfortably tucked under his chin. There was no sign of him being awake but at least he was breathing regularly.

He scanned Shinya's face. The latter was in deep sleep. There was nothing abnormal with the other's face except for the bruise on his lips. There was a short cut on the lower lip but it was nothing life threatening. Other than that, Shinya's lips were slightly swollen from their intense kisses but still, it was nothing major to worry about.

Guren wanted to swipe Shinya's hair off his face but he stopped himself before he could.

Next, he took a quick scan on Shinya's body. Shinya's skin was covered with bruises caused by him. But since they were nothing dangerous or permanent and could be covered under the uniform, Guren braced himself from the thickening guilt inside him.

Guren wetted his lips.

He tried to be as gentle as possible by thrusting slower but it was hard since Byakkomaru would thrust down harder with Shinya's body. Guren had no choice aside from kissing or gnawing at him on the body trying to deliver pleasures when he had the chance just to bring Shinya's attention away from the pain. Guren could not bear seeing Shinya's face that contorted from time to time with tears streaming down his face or listening to his screams that occasionally escaped his lips.

Shinya was slowly healing.

Noticing no sign of Byakkomaru on Shinya, Guren concluded that maybe the demon was 'sleeping' inside him.

Pressing his lips together, he put his hand on Shinya's shoulder and moved him just enough so he could slip out from underneath Shinya's body.

After a quick shower, Guren stood in front of the mirror, staring at his reflection. He looked tired (he barely got into sleep after Byakkomaru forced him a few rounds of sex after the first round). The faint dark circles under his eyes made him look worse.

Then his eyes wandered down to his body. Fingers print from when Byakkomaru choked him marked his neck with a tint of dark purple and angry red trails tainted his body both at the front and at the back. Byakkomaru sure took his sweet time tormenting him by burying Shinya's nails deep into his skin.

He slipped his shirt and started to dress up. At least the marks would remain hidden from anybody's views. Including Shinya.

He started to work on his hair.

He considered leaving without waking Shinya up but Guren had no heart to leave him being clueless. In the end, after making sure he was presentable enough before he reported for duty, he decided it was time to wake the other up.

"Oi, Shinya! Wake up!" He shook his friend's shoulder, careful not to cause any harm to him in case he was still sensitive.

The light-haired man's stirred in his sleep. His eyes fluttered. Shinya opened his eyes, scanning the room in the process and realized Guren was by his side. The dark haired man was looking at him with his eyebrows furrowed at him in worry.

"Guren?" he managed, his voice was hoarse. He rubbed the sleep from his eyes. He was in his room but why was Guren here with him?

"Guren, why are you he – um?" Shinya realized he was nude under the blanket. His lower back stung. Wide-eyed, he instantly turned and looked at Guren.

"Byakko -"

"You should take a shower." Guren cut him and looked away, avoiding his eyes. He grasped his hair that was still damp by the neck and scratched the skin there in guilt. He was glad Shinya was unharmed.

"Yeah…" Shinya managed, lowering his face. The blanket was wrapped around his nude body.

The silence was awkward to both of them.

"I should head off first."

With his face still lowered, Shinya nodded at him.

Guren stood up. He wetted his lips once.

"See you."

Only Guren's heavy footsteps clattering on the hard floor surfaces filled the quiet room. It ended with a soft click of door being shut.

Fin.

Thanks for reading!


End file.
